Lately, a multimode user equipment has become popular. The multimode user equipment is compatible with more than one type of communication service. Using such a multimode user equipment, a user can obtain different types of communication services such as a WCDMA service and a WiBro service with one device. In order to support multiple types of communication services, the multimode user equipment may include a plurality of modulator-demodulators (MODEMs).
When a multimode user equipment moves from one network to another, a handoff is performed to receive a service seamlessly. In order to perform such a seamless handoff, the related art has required all MODEMs in the multimode user equipment to be turned on. Such a requirement greatly increases the power consumption of the user equipment.
In order to overcome such a problem, some of the MODEMs may be turned off when the multimode user equipment is within a network area that the specific MODEMs are not related thereto. However, a user would be required to manually turn on a corresponding MODEM when a multimode user equipment enters a network area that is related thereto. In this case, a service may be interrupted when a user enters into a different type of network area. In order to overcome the above problems, there is a need for developing a method for automatically initiating a handoff from one network to another.